Algicidal substances of Brevibacillus laterosporus and their effect on red tide organisms

Herein, the algicidal effects of Brevibacillus laterosporus on typical red tide organisms were investigated. Through comparative analysis fermentation solution, sterile filtrate and bacterial body, it was found that this strain mainly exerts its function by secreting substances. In paper, we established a method for extracting substances B. systematically investigated their features effect Heterosigma akashiwo . The results showed are mixture compounds all with molecular weights less than 3500 Da, those below 100 Da producing 45% effect; these more polar best extracted methanol. stable over range temperatures (-80.0 to 70.0°C) pH values (4.0-8.0). caused most H. cells rupture within 24 h. remaining cells, activated antioxidant system reduced metabolic activity, leading apoptosis, as observed cell crumbling reduction in membrane potential. responses different algal surface structures also compared analysed. It concluded can act change permeability, allowing entry produce an effect.